Carburetion apparatus



May 22, 1956 M. ERIKSEN 2,746,440

CARBURETION APPARATUS Filed Dec. 16, 1955 United States This invention relates to carburetion in an internal combustion engine and more particularly to a system for vaporizing liquid fuel and supplying the vaporized fuel in combustible mixture to the intake manifold of the internal combustion engine independently of the liquid fuel supply system.

It is an important object of the invention to provide a highly efficient liquid fuel vaporizing and carbureting apparatus by which an internal combustion engine may be started in a conventional manner, then, when the engine has become suiciently Warm from operation, be converted to a vaporor gaseous fuel supply which will operate in a mutuallyexclusive relation with the conventional liquid supply line.

Another object of the'invention is to provide a simple and automatic gaseous fuel supply for a conventional internal combustion engine which will be usable with the conventional throttle to supply the gaseous fuel instead of liquid fuel, properly mixed with air, to the intake manifold of the engine.

It is a further object of the invention to provide means for intimately mixing gas and air,` the gas being vaporizged from the common source of liquid fuel and supplied yto an automobiley intake in preheated and controlled manner which makes for high mileage with a low gasoline consumption. i K

It is a still further object to furnisha safe control system to prevent accidental re or explosion from pre` vheated gas vapors, the system being used in a parallel fuel supply line which will be interrupted and replaced by liquid fuel supply through the conventional fuel system upon they happening of prescribed events such as the stopping of the motor or chilling ofthe exhaust manifold belowa predetermined temperature.

These and other objects and advantages of my invention .will more fully appear from thel following Vdescription made in connection with the` accompanyingdrawings wherein like reference characters refer to similar parts throughout the several views and in which: u i L Fig. l is a schematic view of a conventional internal combustion engine showing. my vaporizing system attached thereto, unessential details being deleted from the view and other hidden parts being designated by dotted lines; v

7ffig. 2 is a diagrammatic representation of the electrical control system in connection with themechanical parts which comprise my invention; and u Fig. 3 isI an enlarged segmental view'of the carburetor and mixing valve element showing in detailftheadjustabilityof the links andv arms which operate the rotary sleeve valve.

Referring now moire' particularly to the drawing, my vaporizer system is intended to be used in conjunction with the conventional carburetor system of an'internal combustionengine and maybe constructed` as a dualtype carburetion or `rnay'be supplied as an attachment` ensemble for adding to= the conventional? engine. rllhe conventional engine is 'shown in Fig. l vwith-special referatento CTL ICC

ence to the fuel system, the engine head and block, as`

well as other parts unessential to an vunderstanding of the engine, having been deleted for the sake of brevity and clarity. An intake manifold 10 has mounted thereon and in internal communication therewith, a carburetor 11 of standard design. The carburetor 11, in turn, has a gasoline float bowl v12`for supplying liquid fuel to the carburetor from a liquid supply line 13. The carburetor 11 also has an internal butterfly Valve 14 which is operated by an'external leverarm 15, generally actuated by aV lever or a cable 16 which in turn is connected to a throttle (not shown) controlled by the driver of the engine. An air cleaner 17 is usually placed over the top of the carburetor so as to catch abrasive material which may be floating in the incoming air. The liquid fuel line `13 leads from a fuel pump 18 which'is capable of maintaining a predetermined constant pressure of fuel in the line.

The inlet of the fuelpump is, of course, connected to the supply line 19 which brings liquid fuel such as gasoline from a supply'tank (not shown).` Another conventional part of the engine which is important in practicing my invention is the exhaust manifold20 which connects with the individual exhaust ports of the engine cylinders (not shown) and directs the exhaust gases to a common outlet 2l which in turn leads to the atmosphere through such other deleted parts as a muffler and an exhaust pipe.

My invention contemplates the addition of several parts and devices which will render the engine convertible to a gas-air mixture Vwhich is presently employed in conven-V tional carburetion. A branch line 22 is placed in uid communication with the outlet of fuel pump 18 through a fixture suchas the cross member 23. The fluid supply line 19 may be furnished with a T 24 as shown.` A bypass line 25 interconnects the cross 23 and T 24 and a spring-loaded valve 26 is interposedin the by-pass line 25. `The valve 26 is set to release at a pressure slightly higher than the cut-out pressure of the fuel pump 18 so thatin normal operation theby-pass need never be employed. in the event, however, the backpressure in either `of lines 22 or 13 exceeds the cut-out pressure of the fuel pump 18 the fluid forwardly of the pump will be by-passed back to the supply line 19.

t he fluid line 22 leads `into a tubular p'ortion'such as the coil or switch back 27 through an orificed fitting 28 in the exhaust manifold 2i). The tubular coil 27 may be supportedwithin theexhaust manifold 2t) by perforated plates or supports 29 and 39 which hold the coil 27vin placebut still allow exhaust gases -to move through freely.

The coil 27 is in heat exchangingrelation with the ex# haust gases from the engine. it is to be understood that the coil 27 can be positioned anywhere in the proximity of the engine provided the coil can pick up'by heat trans- `fer sufficient heat to properly vaporize the liquid fuel.

The outlet ofy the coil .27 leads through the wall of the exhaustmanifold 20 and through a connecting tube 31 to a gas cut-oifvalve 32and thence tothe mixing valve element 33. The tube 3l is preferably housed within an outer bleed tube 34 whichgin turn, is in communication with the exhaust manifold 2l; The bleed tube also may surround the mixing valve` element 33 in fluid tight rela-V tion therewith but having thermal-interconnection soas to'rnaintainthe tube 31, the gas cut-off valve 32 and the mixing valve element 33 hot enough to prevent condensation of gaseous vapors, especially in the wintertime. The bleed line may terminate at a'point of relatively different pressure, such as into the' atmosphere directly or into` another portion of the exhaust manifold as shown.

It is, of course, notessential that a high velocity of ex* haust gas proceed through the bleed line in order to maintain the proper temperature. A certain degreeof thermal conductance will occur between the exhaust manifold 20 and the bleed line 34 secured thereto.'

2,746,440.` Patented `May 22, 1956 The mixing valve element 33' may be so constructed as to interfit in the juncture between theair cleanerV 17 and the carburetor 11, the air cleaner thus being raised slightly bythe height of the mixing valve element 33 as shown'. 'Ihe element 33has a feed valve suchas arotary sleeve valve 35 shown in Figs. l and 3'. The gas admitted through valve 35 is tl'ioroughlyy intermixed withv air inthe portion of; the element 33 which lies beyond the valve 35. Tangential mixing or` bathing, may be used to effect thel mixture of gases, all as it well known in the art and Ido not wish to be restricted'to any particular type of mixing in the mixing Valveelement 33'.

The valve 35' has an outwardly terminating axial' extension to which is secured an adjustable arm 36. The arm 36 is secured' for rotatable adjustment by means of screw 371V The arm 36 is, slotted at 38 for adjusting, by such means as pivot screw 39', one end of a pivotal link 4t1'b`eingin turn pivotally attached at 41 to the arm 15 which actuates. the conventionalfvalve of the carburetor 1I. It will be observed that the same actuation through throttle connection 16 which opens the carburetor valve for acceleration will also open the valve 3'5 for the same purpose (though fuelf can only be, supplied throughone or the other).

In order to disrupt4 flow of liquid fuel through line 13', a liquid' shut-olf valve 42 is provided. After passing through valve 42 the liquid enters float bowl 12. This iloatl bowl isV preferably of specialconstruction, having a conventional chamber 43 and afloat 44 which maintains a constant level of, fuel in the bowl through mechanisrnnot shown. A separate chamber 45 is in uid communication with the rst chamber 43 and a separate float 46 has an extension 4 7 with an abutment 48 which is adapted to close electrical switch 49 as shownin Fig. 2. The electrical` Contact is, thus accomplishedroutside of the float chambers tominimize danger of fire.,V

The circuit diagram for controlling the fuel system isshown separately and diagrammatically in Fig. 2. Thef conventional battery is shown at .50, one pole beinggrounded` and the other connected through leadY 51 and ignition switch 52` to the coil 53. A further lead 54 from lowy voltage line 51. extendsy to the relay switch 55 thenthrough, lead; 56 whengv solenoid 6,5` is re-energized. The

circuit continues through` the tioatI bowl switchv 49.', through lead 57 and solenoid 58fto, ground. 595. Solenoid 58 is withinthe gas cut-off valve, 32of1l`ig-1A and serves to Vopen the. valve 32V whenever energiz edthat is, when the ignition switch-Y 52: i sclosed, when relay switchSS is-,inthe upper closed position with both switches` 62,-.'aud, 63

open` asshown Fig. 2 andwhen switch 49 is also. closed in response to a lowered' predetermined heightv of uid iny fthe, oat bowl. FuelV pump 1S is energized below a predetermined pressure and if ignitionswitchA 52 is on, leads 60. and 61 complete the circuit. A bimetallic switch 62 isk responsiveto apredeterminedtemperature of the exhaust manifold 20, remaining closed until the temperature is reached, then opening asy shown. A switch 63' is in parallel circuit with switchA 6,2 and is actuated by such means as piston 63a in cylinder 63b which inV turn is. interposed across the wall of, and responsive to vacuum ofthe intake manifold 10, the switch 62opening whenever the. engine isrunning and producing an intake vacuum. Either of the parallel switches when closed will energize the lead 64 and relay: coil 65i through ground 59-, WhenI coil 6.5, is energized the switch 55-56 becomes opened andthe switch 55-66 is closed, thus energizing thesignal such as light 67 and solenoidS through ground connec-` tion 59. Solenoid 68 is located inliquid. shut-oifvalve 42 and when ,energizedY maintains valve 42 open, permitting liquid fuelto be pumped; into oat bowl 12. Another signal such as. light 69.-is in` parallel with solenoid., 58- andis energized whenever gas shut-olf valve 32 is opened.

In theoperation of my vaporizing system, the ignition 52 is first closed in thenormal manner, causing the coil 53 to become. conditioned for producinghigh voltage spark to the spark plugs of the engine (not shown). The current continues from the lowvoltagc line 51 through the fuel pump 18 which immediately begins to pump gasoline through the fuel supply line 19 and into the float bowl 12 and into the line 22. The pressure is quickly built up and when the predetermined cut-olf point is reached, the fuel pump will be de-energized. Before the engine is started, both oli the switches'62 and 63 are closed and hence the. relay 65 is. also. energized, maintaining the switch 55-66 in closed condition. The solenoid 68 will thus be energized te:A main-,tain the cut-olf valve 42A in open condition and permitting liquidY fuel to flow i-nto the oat bowl: 12. The gas cut-olf valve 32 remains` in closed condi-tion as: long as'solenoid 58 is not energized. As soon as the engine starts the intake manifold produces a vacuum which will open switch 63. However, since bimetallic switch 62 remains closed until the exhaust manifold reaches a predetermined temperature, the circuit through relay 65 is maintained; Now, however, whenthe exhaust manifold becomes, hot enough to break thel switch contact 62, then the currentV through 65 will be interrupted' and the. relay switch will spring upwardly into the position shown in Fig. 2`. However, since. the float bowl switch 49 is normally in open position, the, engine will'continue run-ning on the liquid fuel which remains in float bowl 12, the de-energized solenoid 68; having shut the liquid' valve 42 to prevent further admission of liquid fuel. When the level of liquid fuel inoat bowl 12' hasdropped suci'ently the abutment 48 on float 4'6 will cause the float bowlY switch 49 to be closed'. This will complete the circuit through solenoid 5S which will then open the gas cut-off valve 32 and convert lthe carburetion system to a gas: interrnixing exclusively.

I't will be noted that if the ignition Switch 52. is turned olf,y or if either the vacuum switch 63 or the bimetallic switch 62 becomes closed, the system will immediately revertl to. the conventional liquid-type carburetion.

It may thus be seen that l have devised a` simple and eicient. apparatus for operating an internal combustion engine. at4 extremely high eciency, yet. preserving the proper degree. of safetyy duringthe operation-thereof.l

It will, of course, be understood that various. changes may be made. in. the form, .details arrangementand proportions of.- the parts without. departingfrom the scope ofV my invention.

. What' l cla-im is:

1 A vaporizer, system for an. internal` combustion engine, having as, conventional elements a source of liquid fuel, a fuel pun-ipl capable, of maintaininga constant fuel line pressure irrespective of engine speed, a carburetor, a, liquid. fuel communication between saidconventional elements, an., intake manifold, an. exhaust. manifold' and athrottle, forA saidcarburetor, said vaporizer system cornprising abranch line leading` from said fuel pump. outlet,y

retor and having a throttle linkagel connected. therewith,

a gas conduit leading from said. tubular' portion to` said mixing valve, a vapor cut-off valve interposed in said conduit for interrupting the ow of gas therethrough,4 and a liquid cut-off in. said liquid. fuelr communicationy between said fuel pump andsaid'f carburetor whereby said vapor system willbe operatively started when the exhaust manifoldhas reached apredetermined temperature, said supply. of liquidfuel: to the. carburetor then being interrupted.

2. A, vaporizer system; for an internal combustion engine having as-V conventional elements a source.- of liquid fuel,l av fuel pump: capableyof maintaining a constant1 fuel line. pressure irrespective of engine speed., a-

float bowl, a: carburetor, a liquid fuel cotrununicationv system comprising Va branch line leading from said fuel pump outlet, a tubular coil in heat transferring relation with the exhaust manifold and in communication with said branch line, a mixingvalve connecting in tandem vapor cut-off valve interposed in said conduit for interrupting the ow of gas therethrough, and a liquid cut-olf valve in said liquid fuel communication between said fuel pump and said iloat` bowl responsive to a delay whereby said vapor system will be operatively started when the exhaust manifold has reached a predetermined temperature and when a predetermined length of time has elapsedfor interrupting the supply of liquid fuel from said float bowl to the carburetor.

3. A vaporizer system for an internal combustion engine having as conventional elements a source of liquid fuel, a fuel pump capable of maintaining a constant fuel line kpressure irrespective of engine speed, a carburetor, a liquid fuel communication between said conventional elements, an intake manifold, an exhaust manifold and a throttle for said carburetor, said vaporizer system comprising a branch line leading from said fuel pump outlet, a tubular coil in heat 'transferring relation with the exhaust manifold and in communication with said branch line, a mixing valve connecting in tandem with said carburetor and having a linkage with said throttle for simultaneous actuation therewith, a gas conduit leading from said tubular coil to said mixing valve, a conduit communicating between the exhaust manifold and the atmosphere for line pressure irrespective of engine speed, a float' bowl, a

carburetor, a liquid fuel communication between said conventional elements, an intake manifold, an exhaust manifold and a throttle for said carburetor, said vaporizer system comprising a branch line leading from said fuel pump outlet, a tubular coil in heat transferring relation with the exhaustmanifold and in communication with said branch line, a mixing valve connecting in tandem `with said carburetor and having a linkage with said throttle for simultaneous actuation therewith, agas conduit leading from said tubular coil to said mixing valve, t a vapor cut-off valve interposed in said gas conduit for interrupting the flow of gas therethrough, a liquid cut-off valve in said liquid fuel communication between said carburetor` and said fuel pump, an instrumentality for operating said liquid cut-off valve and a oat bowl switch i for delaying the opening of said vapor cut-olf valve wherebleeding a portion of the hot exhaust gases therefrom,

said gas conduit being in ',heat transferring relation with said exhaust manifold conduit for maintaining the gas therewithin at an elevated temperature, a vapor cut-off valve interposed in said gas conduit for interrupting the flow of gas therethrough, and a liquid cut-olf valve in said liquid fuel communication between said fuel pump and said carburetor responsive to a time delay whereby said vaporizer system will be operatively started when the exhaust manifold has reached a predetermined temperature and when a predetermined length of time has elapsed, said supply of liquid fuel to the carburetor then being interrupted.

4. The subject matter ofclaim l, and a by-pass communicating with the outlet of said fuel pump and having therein a pressure release valve set to permit fluid fuel to be by-passed back to said liquid fuel supply line when a predetermined pressure has been attained in the pressure by said vaporizer system will be operatively started when the exhaust manifold has reached a predetermined teru-` perature and when said oatbowl switch has allowed a predetermined length of time to elapse, said supply of liquid fuel to the carburetor thenbeing interrupted.

6. A vaporizer system for an internal combustion engine having as conventional elements a source of pressurized liquid fuel, a carburetor, a liquid fuel line leading from the source of pressurized liquid fuel to the carburetor, and an engine area subject to heat of combustion during operation of the engine, said vaporizer system comprising, a branch line leading from said source of pressurized liquid fuel, a tubular member secured in heattransferring relation with said engine area subject to heat of combustion for vaporizing liquid fuel supplied thereto, a mixing valve connecting in tandem with said carburetor and having throttle means for actuation thereof, a `gas conduit leading from'said tubular member to the mixing valve, a vapor cut-off valve interposed in said conduit for interrupting the flow of gas therethrough, a liquid cut-olf in Ysaid liquid fuel line between the source of fuel p Y and said carburetor, and means in thermal association with the exhaust gases of the engine responsive to heat transfer therefrom to initiate a supply of vaporized fuel A to said :carburetor and to interrupt the supply of liquid i fuel to the carburetor. l

7. The subject matter of claim 6, and meansresponsive to change in gas pressure with stopping of engine operation to interrupt said supply of vaporized fuel to said carburetor and to re-establish the supply of liquid fuel thereto. Y

References Cited inthe le of this patent l UNITED VSTATES PATENTS y `2,315,882 Trimble et al. Apr. 6, 1943 

